Acrilla semicostata explained

Acrilla semicostata is an extinct species of sea snail, a marine gastropod mollusk in the family Epitoniidae, the wentletraps.

Description

(Original description) The seven whorls are contiguous. The spire is transversely striated with numerous, slightly raised ribs. The lower part of each whorl is smooth and naked. The ribs scarcely cover two-thirds of each whorl. ^[1]

Distribution

Fossils of this marine species have been found in Eocene strata in Val-d'Oise, France and in Barton on Sea, Great-Britain.

References

• Cossmann (M.) & Pissarro (G.), 1907 - Iconographie complète des coquilles fossiles de l'Éocène des environs de Paris, t. 2, p. pl. 1-9 (
• Le Renard (J.) & Pacaud (J.-M.), 1995 - Révision des Mollusques paléogènes du Bassin de Paris. 2 - Liste des références primaires des espèces. Cossmanniana, t. 3, vol. 3, p. 65-132

Notes and References

1. https://www.biodiversitylibrary.org/bibliography/14408 Sowerby, J. (1812-1815). The mineral conchology of Great Britain; or coloured figures and descriptions of those remains of testaceous animals or shells, which have been preserved at various times and depths in the earth (Vol. I). London, privately published, pp. i-vii, 9-234 + index